What is this pattern called?

unknownpattern.js

(function (global, factory) {
    factory(global.MyFunc = {});
}(this, function (myfunc) {
    // private
    var privVar = 'What\'s this pattern called?';
    function privFunc (some, text) {
        return some + text;
    }
    
    // public
    myfunc.prop = privVar;
    myfunc.method = function (some, text) {
        return privFunc(some, text)
    };
}));

document.getElementById('question').innerHTML = MyFunc.method("I have a question... ", MyFunc.prop);